There is considerable advantage in prefabricating the railings and balusters for a fence or guardrail, whereby these elements can be erected on site with a minimum of tools and fasteners and the like.
There have been many examples of guardrail kits designed to avoid separate fasteners. An early version of such a kit is described in my U.S. Pat. No. 4,334,671 issued Jun. 15, 1982. Other such guardrails are illustrated in U.S. Pat. No. 4,390,164 Cokelekoglu, issued Jun. 28, 1983; U.S. Pat. No. 4,451,025 Spera, issued May 29, 1984; U.S. Pat. No. 4,586,697 Tornya, issued May 6, 1986 and U.S. Pat. No. 4,805,879 Spera. All of these patents describe clip-on type kits, having a plurality of balusters to which the top and bottom railings can be snapped on.
However many of the kits referred to above have require special tools to erect the guardrails. Other available kits require several parts, making assembly complicated and generally requiring experts.